A stable Surface-enhanced Raman Scattering (SERS) substrate with high enhancement is key in a Raman detecting system. A typical SERS substrate is usually composed of rough metal surface or coupled metal particles. The SERS substrate can be fabricated by means of a wet-state process and depositing Ag particles on a multi-walled carbon nanotube (MWCNT)-alumina-coated silica film. However, the method usually leads to some defects and lower sensitivity of the Raman detecting system.
What is needed, therefore, is to provide a Raman detecting system having higher sensitivity.